In various fields of graphics such as the production of moire grids, reticle and the like it is necessary to form precise patterns where it is necessary that the pattern be of like and uniform dimensions and tolerances throughout the graphic representations and that the geometric position or phase position of all the portions of the pattern be precise. Specifically in these graphics it is necessary that the position and dimensions at one corner of the graphic representation be precisely in phase with the position of other portions at other corners or near the center of the graphic representation and that the dimensions throughout be accurate within extremely close tolerances.
One field of use where the geometric identity is extremely demanding and the demands are well known in the art is in hologram production. A hologram is essentially a pattern of fringes which must be in phase with each other throughout the hologram. The fringes in various parts of the hologram must be equal, and the spacing from center to center of the fringes must be accurate. Inaccuracies of dimension or phase from one point to another will result in a fuzzy recreation of the object represented in the hologram.
Where graphic representations are required in micro size, as they are for example in holography, it is usual to for such patterns in large scale or macro representation and reduce them optically for recording to produce the micro graphic. Unfortunately, optics for such micro reduction characteristically may not produce accurate geometric positioning, design and dimension throughout a large broad area, and distortion is ordinarily expected, particularly in positions close to the perimeter of the graphic representation in reference to positions closer to the center or opposite side of the perimeter.